African-American (AA) women have a higher incidence of many cancers (e.g., colon, pancreas) and higher cancer mortality (e.g., breast, colon, pancreas) relative to other American women, and many of these differences are unexplained. The Black Women's Health Study (BWHS), the largest follow-up study of AA women, was begun in 1995 to provide relevant information on these racial disparities. 59,000 AA women ages 21-69 from 17 states enrolled by completing health questionnaires. The BWHS has successfully followed them for cancer through biennial questionnaires and linkage to 24 cancer registries in the states in which >95% of participants live. Data have been collected on numerous potential risk factors (e.g, medical, reproductive, lifestyle, psychosocial, socioeconomic, air pollution). Cancer diagnoses are validated by hospital and cancer registry pathology data. A DNA/oral microbiome biorepository contains saliva-mouthwash samples from 26,800 participants. Blood sample collection, in progress, has obtained blood samples from 9,300 participants to date (14,000+ expected) . Breast tumor tissue has been collected for 750 incident breast cancers. The study has identified 5,631 incident cancers to date, including 2,651 breast cancers. The study has published extensively on nongenetic and genetic risk factors for breast cancer and other cancers. Because participants were young at baseline (median age = 38), accrual of less common cancers was slow. Participants have now reached ages of high cancer incidence, meaning that sufficient numbers will be accrued for informative assessment. This infrastructure proposal has 3 aims: (1) continue and enhance follow-up and data collection in the BWHS, adding information (including Medicare data) on cancer treatments and outcomes (2) manage and enhance biologic sample collection by adding additional samples to the saliva/mouthwash and blood repositories, collecting tumor tissue for all solid cancers in addition to breast cancer, collecting full-field digital prediagnostic mammograms, and genotyping with a genome-wide array all incident cancer cases for which we have a DNA sample (~2,800) together with an equal number of controls with DNA; (3) share the data in consortial projects. Continuation of the BWHS is a high priority because: a) 89% of participants are still cancer-free due to the young age at baseline; b) follow-up has been successful and unbiased ; c) the BWHS can assess the effects of exposures (e.g., class 2 and class 3 obesity, premature birth, experiences of racism) that are less prevalent in other populations; d) increasingly large numbers are needed to study scientific questions and BWHS genetic, nongenetic, and biospecimen data will contribute to numerous consortia to study a range of cancers; e) the BWHS has a record of high productivity; f) further work is needed to understand numerous racial disparities in cancer incidence and survival. In sum, continuation of the BWHS will contribute appreciably to knowledge about cancer etiology and survival in an underserved population; the biolospecimen and mammogram repositories will contribute greatly to that effort, as will participation in consortial studies.